1. Field of the Invention
The present invention is related to a wireless sub-surface sensor having a radio for performing real-time soil measurements.
2. Description of the Related Art
The prior art discusses other irrigation systems and methods.
Closing an underground to above ground RF communication link is a challenging task. The challenge is typically due to difficult propagation conditions perpetrated by high water content as well as high conductivity in the soil.
The moisture and conductivity vary over time depending on environmental stimulus. High water content increases the rate of absorption of RF energy. Salinity and moisture both change the die-electric constant of the soil, effectively detuning the antenna element as water content changes over time.
In instances, it is possible to adaptively modify the antenna tuning elements, to attempt to tune the antenna to the current state of the soil.
However, in some instances it may not be possible to overcome the adverse effects of moisture in the ground by direct tuning of the RF and antenna components on board the underground wireless sensor. In other instances, certain wireless sensing devices may not be able to adapt their tuning in close to real time to match the soil conditions.
The Present Invention seeks to resolve the problems of the prior art.